A prior cutting tool comprises:
two pairs of jaws for holding the optical fiber to be cut at two points, each pair of jaws comprising a stationary jaw and a moving jaw, with the moving jaw being guided in translation by cylindrical rods sliding in holes in the jaw;
a first mechanical device for moving the two jaws in each pair slightly apart so as to enable an optical fiber to be inserted between the jaws;
an "anvil" piece in the form of an arc of a circle situated between the two pairs of jaws and displaceable to be applied against the optical fiber when the fiber is held in position by the two pairs of jaws;
a second mechanical device for applying the anvil against the fiber;
a diamond chisel displaceable to be applied against the optical fiber with predetermined force to initiate cleaving, with cleaving being finished off by the tension set up by the anvil; and
a third mechanical device enabling the chisel to be applied against the fiber.
These three mechanical devices are actuated independently to displace the following in translation, respectively: the two pairs of jaws; the anvil; and the diamond chisel. These three translation motions are performed in succession and in that order. In conventional hand tools, these three mechanical devices suffer from being bulky and inconvenient to use since the three devices must be operated successively and in the proper order. Prior tools also suffer from the drawback of sometimes polluting the end of the optical fiber since the fiber may easily encounter dust while being inserted into the narrow space left between the jaws when the jaws are apart.
In other prior types of fiber-cutting tool, the fiber must be inserted in a capillary tube, but such insertion is difficult and the risk of polluting the fiber is high.
The three mechanical devices of prior tools suffer from wear, thereby degrading cutting accuracy as wear increases since fiber positioning becomes more and more inaccurate. In addition, the complexity of the mechanical devices makes it practically impossible for the purchaser of the tool to maintain on these devices, so the tool must be returned to the manufacturer for maintenance. Finally, prior tools suffer from being specialized in that they are suitable only for cutting either a fiber that has been bared or else a fiber that still includes its protective covering almost to the cutting point. For a fiber still in its covering, one of the pairs of jaws is of a size suitable for clamping the fiber and its covering while the other pair of jaws is of a size suitable for clamping to the end of the fiber which has been bared over a length of a few centimeters.
An object of the invention is to remedy these drawbacks in prior tools for cutting optical fibers.